Baixe Física é o princípio de tudo e outras Notas de estudo em PDF para Cálculo, somente na Docsity!
AUXILIARY VERBS
There are three types of auxiliary verbs in English:
A.- TO BE, TO HAVE, TO DO. * They are main verbs:
I am happy / We have it / We do the washing.
* But sometimes they are the auxiliary to form:
-- continuous tenses. I am writing.
-- passive voice. It is done.
-- perfect tenses. She has gone.
-- negative and interrogative sentences.
I don’t know. Does she go there?
B.- WILL, SHALL, WOULD. They are never main verbs. They are used to form tenses:
-- WILL, SHALL, future. It will rain.
-- WOULD, conditional. He would stay here.
C.- CAN, COULD, MAY, MIGHT, SHOULD, OUGHT TO, MUST, HAVE TO(**), NEED. They
are MODAL VERBS.
* They aren’t the main verb and don’t form tenses.
* They help the main verb to explain some aspects (ability,
possibility, prohibition …)
* They are followed by infinitive (without “to”)
* They are defective:
-- They haven’t got “s” in the 3
rd
. person singular.
-- “ “ “ infinitive, gerund, participle.
-- We don’t use DO in negations and questions.
-- Two modal verbs can’t be together in the same sentence.
(**)HAVE TO is a semi-modal verb. It may have a similar meaning to a modal,
but it takes “s” in the third person singular: He has to go now; negatives
and questions are formed with the auxiliary do: Do you have to go now?
ABILITY POSSIBILITYPERMISSION
ADVICE OBLIGATIONNECESSITYPROHIBITIONDEDUCTIONREQUESTS
OFFERS SUGGESTIONS
WILL SHALL ^ WOULD
CAN ^ ^ *
COULD ^ ^ ^ ^
MAY ^ ^
MIGHT ^
SHOULD
OUGHT TO
MUST ^ *
HAVE TO ^ *
NEED
in negative form
Uses
CAN Ability, capability and knowledge to do something
You can’t open the door. It’s closed Sarah can play three instruments
COULD
General ability in the past. But in negative it’s for general and particular situation
When I was younger, I could run 10 km She couldn’t speak French. She couldn’t speak to me yesterday When CAN or COULD aren’t possible. I will be able to study more
ABILITY
TO BE ABLE TO
In past it’s used in a particular situation
When I saw the dog, I wasn’t able to run CAN Things that are (not) permitted The class is over. You can leave now More formal. (in a shop) Could I have a look? COULD It isn’t used to give permission Of course, you can/may. MAY Very formal May I ask you a personal question?
PERMISSION
TO BE ALLOWED
TO
When the rest aren’t possible I won’t be allowed to do that, sure.
MUST
Only in present (when the subject puts the obligation You must stay here In present when the obligation is external I have to stay in bed. Doctor’s order
OBLIGATION
HAVE TO
NEED TO
for the rest of the tenses Did you have to buy this?
PROHIBITION MUSTN’T/CAN’T Obligation not to do something You mustn’t smoke here
In affirmative it’s a normal verb He needs to rest sometimes NEED (TO) (^) In negative you can use the normal verb o the modal one
You don’t need to carry heavy things You needn’t carry heavy things DON’T HAVE TO It’s not necessary You don’t have to carry heavy things
NECESSITY
HAVE TO In future You’ll have to stay in hospital for surgery
SHOULD
To ask for and give advice. In past, use perfect infinitive
You shouldn’t smoke so much You are ill, you shouldn’t have smoked
ADVICE
OPINION
OUGHT TO Stronger than SHOULD You oughtn’t to smoke so much Certainty It could rain In negative means impossibility You couldn’t run a marathon
CAN
COULD
BE ABLE TO (^) Speculating about the past You could have run faster last day
MAY Less possible Speculating about the past
It may rain Yesterday it may have rained
POSSIBILITY
MIGHT
Remote possibility. Speculating about the past
It might rain Yesterday it might have rained
MUST
We are sure or for speculation In past
I must have flu DEDUCTION She must have had flu CAN’T We’re sure something isn’t true In past. Disbelief
He can’t be your husband He can’t have been/couldn’t have been CAN Informal Can I borrow your pen?
REQUEST COULD Polite Could you close the door, please?
WOULD/WILL/MAY More polite Will you give me some money?
OFFERS WOULD^ Polite^ Would you like more coffee? SHALL First person Shall I open the door? SHOULD OUGHT TO
Similar to giving advice You should /ought to save more SUGGESTION money if you want to buy a car
SHALL / COULD First person Shall we dance?
NEED (TO)
Need
Note from the above examples that need can either act as a modal verb or as an ordinary verb.
When it acts as a modal auxiliary verb it is nearly always used in negative sentences, as the above
examples illustrate, although it is sometimes also used in questions as a modal verb:
Need you leave straightaway? Can't you stay longer?
Need I say more? I would like you to stay.
When it is used as an ordinary verb with to before the following infinitive and with an s in the third
person singular, it appears in both affirmative and negative sentences and in questions:
She's almost dehydrated. She needs a drink. She needs to drink something before she has anything to
eat. She doesn't need to stay in bed, but she should have a good rest before she sets off again. ~ Do I
need to stay with her? ~ Yes, I think you should
Needn't and don't need to
There is a difference in use when these verbs are used to describe present situations. We can use both
needn't and don't need to to give permission to someone not to do something in the immediate future.
We can also use need as a noun here:
You don't need to water the garden this evening. It's going to rain tonight.
You needn't water the garden this evening. It's going to rain tonight.
There's no need to water the garden this evening. It's going to rain tonight.
You don't need to shout. It's a good line. I can hear you perfectly.
You needn't shout. It's a good line. I can hear you perfectly.
There's no need to shout.. I can hear you perfectly.
However, when we are talking about general necessity, we normally use don't need to:
You don't need to pay for medical care in National Health Service hospitals.
You don't need to be rich to get into this golf club. You just need a handicap.
Needn't have and didn't need to
Both forms are used to talk about past events, but there is sometimes a difference in use. When we say
that someone needn't have done something, it means that they did it, but it was not necessary. Didn't
need to is also sometimes used in this way:
You needn't have washed the dishes. I would've put them in the dishwasher.
You didn't need to wash the dishes. I would've put them in the dishwasher.
But we also use didn't need to to say that something was not necessary under circumstances where it
was not done:
The sun came out so we didn't need to take any raincoat on the trip.
Had Better / Should
You'd better tell her everything.
Although had is the past form of “have”, we use had better to give advice about the present or future.
I'd better get back to work.
We'd better meet early.
The negative form is had better not.
You'd better not say anything.
I'd better not come.
We use had better to give advice about specific situations, not general ones and it is more coliquial. If
you want to talk about general situations, you must use should.
You should brush your teeth before you go to bed.
I shouldn't listen to negative people.
When we give advice about specific situations, it is also possible to use should.
You shouldn't say anything.
I should get back to work.
However, when we use had better there is a suggestion that if the advice is not followed, that something
bad will happen. You can also translate it MÁS VALE QUE + verbo en subjuntivo
You'd better do what I say or else you will get into trouble.
I'd better get back to work or my boss will be angry with me.
We'd better get to the airport by five or else we may miss the flight.
HAD BETTER + INFINITIVE without “to” = es/sería mejor que + verbo en subjuntivo
